Yantai Bonway Manufacturer

AC Motors

High voltage motor

1. Big and Medium Size High Voltage Induction Asynchronous AC Electric Motor Introduction

High-voltage explosion-proof motor is a kind of motor which can be used in inflammable and explosive factory. High-voltage explosion-proof motor is mainly used in coal mine, petroleum and natural gas, petrochemical industry and chemical industry. In addition, it is widely used in textile, metallurgy, city gas, transportation, grain and oil processing, paper making, medicine and other departments. As the main power equipment, high-voltage explosion-proof motor is usually used to drive pumps, fans, compressors, vibration screens and other transmission machinery. With the development of science and technology and production, the places of explosion danger are increasing.

For example, the production of edible oil used to be using the traditional pressing process, after the 1970s, China began to introduce foreign advanced oil extraction process, but this process should use hexane chemical solvent, hexane is flammable and explosive substances; Therefore, the oil extraction workshop is a dangerous place for explosion, which requires the use of high-voltage explosion-proof motors and other explosion-proof electrical products. For example, in recent years, China's highway development is rapid, a large number of fuel gas stations appear, also provides a new market for high-voltage explosion-proof motor.

2. Product Classification

According to the High voltage motor principle: can be divided into high-voltage explosion-proof motor., explosion-proof synchronous motor and explosion-proof dc motor.
It can be divided into hv explosion-proof motors for underground coal mine and high-voltage explosion-proof motor. for factory.
According to the principle of explosion proof: can be divided into flameproof motor, increased safety motor, positive pressure motor, no spark motor and dust high-voltage explosion proof motor.
According to the host of form a complete set points: can be divided into the coal mine conveyor with high-pressure, coal mine explosion-proof electric motor hoist with high voltage explosion-proof motor, mucker with high voltage explosion-proof motor, coal mine local fan used high voltage explosion-proof motor, valve with high voltage explosion-proof motor, fan with high voltage explosion-proof motor, Marine high-voltage explosion-proof motor, lifting metallurgical high voltage explosion-proof motor and hydrogenation type matching with increased safety brushless excitation synchronous motor, etc.

In addition, it can also be classified according to rated voltage, efficiency and other technical indicators, such as high-voltage high-voltage explosion-proof motor, high-efficiency high-voltage explosion-proof motor, high-slip high-voltage explosion-proof motor and high-torque high-voltage explosion-proof motor. This paper is classified according to the principle of explosion protection.

High voltage motor is a motor with rated voltage above 1000V.6000V and 10000V voltages are commonly used. Due to the difference of foreign power grids, there are also 3300V and 6600V voltages.The high-voltage motor is produced because the High voltage motor power is proportional to the product of voltage and current. Therefore, the power of low-voltage motor increases to a certain degree (such as 300KW/380V), and the current cannot be expanded or the cost is too high due to the limitation of the allowable bearing capacity of the wire.High power output needs to be achieved by increasing the voltage.The advantages of high voltage motor are large power, strong impact resistance;The disadvantage is high inertia and difficulty in starting and braking.

Rated voltage 6300V 10000V high voltage motors excellent point power, strong impact withstand point inertia, start and brake are difficult

High - voltage motors can be used to drive various kinds of machinery.Such as compressor, water pump, crusher, cutting machine tools, transport machinery and other equipment for mining, machinery industry, petrochemical industry, generators and other industries as prime mover.the High voltage motor used to drive blower, coal mill, steel rolling mill and winder should indicate the purpose and technical requirements when ordering, and adopt special design to ensure reliable operation.

High voltage motor is divided into: high voltage synchronous motor;High voltage induction motor;High voltage asynchronous wound motor;High voltage squirrel cage motor, etc.

Control device

According to actual way: size and power capacity and 1000 kw motor capacity can be directly below the start, then the impact of the current rating is 3 to 6 times. In order to prevent the surge current is too large, reduce the starting current must be considered for large motor startup mode: have a bunch of reactance starting, frequency conversion start, a variety of ways such as hydraulic coupling start. There are complex simple, price difference is very big. Due to their high voltage, large current shock, motor manufacturing must meet the requirements of overvoltage, insulation level is higher.Need to use double imine high voltage motor according to the voltage grade, single imide, thin BaoBian line double wire and so on all kinds of silk, material all ready, can be made in coiling machine winding spindle type into a circle, general motor coil linear section 25 cm, shortest maximum coil linear section 1.2 meters, winding can be plain, ChanLi around, also can double flat transposition around, also can double flat transposition stand around, according to the specific requirements.The round enameled wire coil can also be wound by using the universal adjustment in the disc.Winding machine built a speed regulating motor and a gear reducer, drive the winding machine of 0-120 r/min can be good or poor braking rotation, and can be positive and negative count, can generally be winding of 1600 kw motor coil, the other with a simple tension bridle device, can control winding firmness of wire coil, general repair factory choose above products, such as when you meet the special large specification can choose different winding equipment.

After winding the shuttle coil of high voltage motor, wrap it with shrink belt, yellow wax silk belt and other insulating materials to protect the insulation outside the coil, between layers and turns from damage.During the drawing machine, avoid the friction of the die fixture, nose pin, etc., to prevent loose deformation.

Wrap up coil to use workwoman commonly, because workwoman is careful and skillful and work speed is fast, 3-5 people wrap up to offer pull model commonly.Electric tape wrapping machine can also be used.

Comparison of different series Big Size Three Phase MV HV HT Medium/ High Voltage Induction AC motors

No.	Squirrel-cage motor	Y JS	YKK	YKS	Y2 YJS
No.	Slip ring motor	YR JR JR2	YRKK	YRKS	YR2 YR3
1	Structure	Box-type construction, made up of steel plates welded with each other			Compact struction
2	Cooling method	IC01 or (IC11, IC21, IC31)	IC611 or IC616	IC81W	IC411
3	Cooling method	Natural ventilation, with top mounted protection cover	With top mounted air-air cooler	With top mounted air-water cooler
4	Protection type	IP23	IP44, IP54, IP55	IP44, IP54, IP55	IP54, IP55
5	Insulation	F
6	Mounting arrangement	IMB3, IMV1, IMB35
7	Voltage available	380~690 V, 2400 V 4160 V, 3 kv, 3.3 kv; 6 kv, 6.3 Kv 6.6 kv; 10 kv, 11 kv
8	Frequency available	50 Hz , 60 Hz

Type forming machine, go up, pull type machine is a machine, its main purpose is to put the coiling machine winding set around the spindle type or level wound coil spindle type coil into a box line coil, coil box type on the basis of motor stator iron core inside and outside the circle, composed of centripetal type Angle coil, winding type bobbin coil 2 technicians to complete, and type (+) usually need to three people.Before the drawing, a computer will draw the coil shape according to the actual situation of the High voltage motor under repair and make it into a template for adjusting the drawing machine. People who do not draw generally use the old coil as the template to adjust the drawing machine.

Due to the addition of different layers of mica insulation material, the thickness of the high-voltage motor increases a lot, and the distance of the coil end is occupied by the insulation layer. If you don't pay attention to it, you will not be able to insert the wire when it is crowded, which makes it difficult to insert the wire.Cold mold (or called positive mold), the traditional wooden, each type of motor needs to make a set of mold, and my company used the positive mold with adjustable distance, adjustable Angle, high adjustable end flexibility.During the normal beating must pay attention to, do not damage the insulation between layers.

After the low-voltage motor is drawn, it is generally no longer cold adjusted, and directly enters the embedding process.

1. It is convenient to insert lines after setting.

2. The coil can be moisture-proof and waterproof when solidified.

3. Corona discharge beyond the notch.

4. Complete the closure to the outside world and avoid high pressure breakdown.

Our company produces the hot press molding machine length 1.2 meters, up and down, about, Angle can be adjusted.After the customer has a fully automatic computer-controlled hot press, all the YR,JR,JS,TDK and stator coils of the High voltage motor can be processed within 1600KW.And can be customized according to customer requirements special machine.

Hot press can be additional automatic control device, such as H level temperature in the number of degrees of constant temperature work, F level in the number of degrees of constant temperature work, hot press time factory, when the boot, when standby insulation can be realized intelligent, hot press to prepare for the designated manufacturers to buy some mold release agent, cleaning agent, cleaning residue and other tools.

The hot press coil should be placed for a period of time to test the withstand voltage, which is a procedure of product inspection. According to 3000V, 6000V, 10000V and other working voltages, there are different requirements on the withstand voltage standard.

How to prevent the straight part or the curved part to break through, send some must be mastered in the hot press, our company mastered the small repair high voltage motor coil several skills, master the dozen withstand pressure after breaking to copy the coil skills, this needs to participate in the study of a section will know.

The instrument that beat withstand pressure, the product of wuhan area of general choose and buy is more.

From the winding coil to the end of embedding, an extra coil is generally made for the following purposes:

1. Leave the technical data of the High voltage motor (wire gauge, turns, insulation thickness, straight line length, curvature, end length, lifting height and pitch Angle, etc.).

2. In case which coil is unqualified, replace it.

The high voltage motor is usually 200KW - 2000KW, the weight is more than 3 tons, according to their own conditions can be designed appropriate line crane, so as to facilitate the maintenance of the High voltage motor.

Embedded wire (stator and rotor)

Motor stator and rotor after dust removal (generally by high pressure water gun flushing) into the oven baking, cooling after the High voltage motor is determined to be minor or major repair.When the hv motor is in small repair, one set of small repair is proposed for coil tool, rotor guide line bending tool and stator coil movement hot press tool.How not to damage the coil is the key.It takes time and effort to reprocess the removed coil. Whether the old coil can be reconstructed is the key to save time (the procurement cycle of the silk covered wire used by the general high-voltage motor is 1 to 2 weeks, which delays the repair time.

In minor repair of the rotor, how to remove the copper guide bar (aluminum bar) in the rotor, how to replace it, how to wrap up the standard coil, and how to weld the test and a series of other procedures, are not discussed here.When the High voltage motor rotor is overhauled, all the coils must be taken out. How to take and keep the coils intact is the key technology.For example, high voltage motor, to be as complete as possible out.If the wire gauge is not damaged, it can save money and time when repacking.When the coil needs to be remanufactured, the wire gauge must be worked out, wasting time.When the stator inlays the wire, the pressure is normally put on every three coils to prevent the coil from discharging on the grooves at both ends or on the rings at both ends, as well as the coil damage caused by the fault of the downline.The wiring, spacing, grouping, wiring, bandaging, star connection, motor lead and other operations after the whole coil is embedded are carried out in accordance with the operating procedures of each grade of motor.General motor in the sealing star point before hit a withstand voltage, that is, sealed together, three lead wire can be.There are also 6 special leads for sealing triangle or connecting star.General lead wire to be purchased from the designated high voltage cable manufacturer.All embedded wire wiring is completed, the whole motor is finished once again.

Motor manufacturers mass production of motor, to buy vacuum immersion paint equipment, the equipment provided by professional manufacturers.General repair manufacturers use electric heating rod to heat the stator to a certain temperature after the reversal of the stator mouth upward for double-sided painting.There is a paint holding device at the bottom when painting.After filling the paint, it needs to wait for more than two hours before putting it into the oven, and then bake for three hours at low temperature and 18 hours at high temperature.After 24 hours.The purpose is to insulate the solidified wire rod from the inside and outside of the groove to prevent vibration from damaging the insulation structure.Please remove the residual paint in the stator cavity and assemble.

Machine parameter test: use the patented technology -- magswitch transformer starting test equipment to start various motors such as 380V, 660V, 1140V, 3000V, 6000V and 10000V, with the capacity of high and low voltage starting test within 1000KW.Every squirrel cage, slip ring motor can be no-load start, no-load running test, test items are divided into measuring current, measuring voltage, measuring speed, measuring temperature, measuring noise and more than a dozen items.

The domestic xiangtan electric machine factory, Shanghai electric machine factory, Harbin electric machine factory and so on are the domestic high voltage electric machine famous brand

Speed control technology

From the market situation, high voltage motor speed regulation technology can be divided into the following:

Hydraulic coupler

The impeller is added between the High voltage motor shaft and the load shaft to adjust the pressure of the liquid (generally oil) between the impeller to achieve the purpose of adjusting the speed of the load.This control method is essentially the slip power consumption, its main shortcoming is decreased efficiency with the rotating speed is more and more low, need to disconnect the High voltage motor and load for installation and maintenance workload is big, over a period of time requires to change the shaft seals, bearing and other parts, the scene were generally dirty and appear equipment level is low, belongs to the technology.

Early interest in speed regulation technology manufacturers, either because there was no high pressure speed regulation technology to choose from, or to take into account the cost factors, the hydraulic coupler has some applications.Such as water company pumps, power plant boiler feed water pumps and induced draft fan, steel plant dust removal fan.Nowadays, some old equipment has been gradually replaced by high voltage frequency conversion in transformation.

Siemens range of high voltage motors can satisfy your every need. All HV motor systems from our extensive portfolio deliver superior reliability and long service
Electric manufactures a wide range of high-voltage motors, providing our customers with the best motor for their environment and operating conditions.
Voltage motors meet the specifications of the harmonized standards. Thus, the product lines comply with the Ecodesign requirements
There's a mixture of different motors, which include both low- and high-voltage designs. Learn the ins and outs of these mechanical
We supply high-voltage motors from 3 kV to 13.3 kV and up to a power of 40,000 kW. We implement your motor projects in close cooperation with you

High and low frequency converter

Inverter is a low-voltage inverter, which USES input step-down transformer and output step-up transformer to realize the interface with high-voltage power grid and motor, which is a transition technology when high-voltage frequency conversion technology is not mature at that time.

Because the voltage of the low-voltage converter is low, the current cannot rise indefinitely, which limits the capacity of the converter.Due to the existence of the output transformer, the efficiency of the system is reduced and the floor area is increased.In addition, the magnetic coupling ability of the output transformer is weakened when the frequency is low, so that the frequency converter is weakened when it is started.For the harmonics of the power grid, 12 pulse rectification can reduce the harmonics, but it cannot meet the strict requirements of harmonics.Output transformer in the boost at the same time, the frequency converter to generate dv/dt is also the same amplification, must be equipped with a filter to apply to the ordinary motor, otherwise it will produce corona discharge, insulation damage.This situation can be avoided by using special frequency conversion motors, but it is not as good as using high and low frequency converters.

High and low frequency converter

The inverter is a low-voltage converter. The transformer on the input side changes the high voltage into low voltage, and the high-voltage motor is replaced. Special low-voltage motor is adopted.

Due to the use of low-voltage frequency converter, the capacity is relatively small and the harmonics on the side of the power grid are relatively large. Therefore, 12-pulse rectification can be adopted to reduce the harmonics, but it cannot meet the strict requirements on harmonics.When the frequency converter fails, the High voltage motor cannot be put into the power grid operation, and there will be problems in some applications where the machine cannot be shut down.In addition, the High voltage motor and cable should be replaced, the amount of engineering is relatively large.

This speed regulation method has a form of change, namely internal feedback speed regulation system, which eliminates the inverter part of the transformer and makes the feedback winding directly in the stator winding. This method requires the replacement of the High voltage motor, and the performance of other aspects is similar to cascade speed regulation.

Because of the influence of rotor slip-ring, cascade speed regulating motor cannot achieve great power and the maintenance workload of slip-ring is also large.

Current source type direct high voltage inverter

The inverter adopts thyristor on the input side for rectification, inductive energy storage, and SGCT on the inverter side as the switch element, which is a traditional two-level structure.Because of the device's limited pressure level, multiple devices must be used in series.Device serialization is a very complex engineering application with low theoretical reliability, but some companies can go as far as production.Since there are only two levels on the output side, the dv/dt borne by the High voltage motor is large, so an output filter must be adopted.The multi-pulse rectifier on the power grid side is optional and the user needs to make requirements according to his own factory situation.The main advantage of this converter is that it can feed the inertial energy of the load back to the grid without additional circuitry.

The main disadvantages of current source inverter are low power factor, high harmonic, and change with the change of working condition.

3. Characteristic

high-voltage explosion-proof motor use flameproof enclosures to separate the electrical parts that may produce sparks, arc, and dangerous temperatures from the surrounding explosive gas mixture. However, the enclosure is not hermetically sealed, and the explosive gas mixture surrounding it may enter the High voltage motor through the gap between the mating surfaces of the enclosure parts. Explosion may occur when it comes in contact with ignition sources such as spark, arc and dangerous high temperature inside the enclosure.

At this time, the flameproof enclosure of the High voltage motor will not be damaged or deformed, and the explosive flame or hot gas will not ignite the explosive gas mixture around when it passes through the gap of the bonding surface.

Summarize

There are many kinds of explosion-proof motors. In the environment of explosion hazard area, the selection of explosion-proof motors is very important to ensure safe production. When choosing explosion-proof motor, the explosion-proof performance must be understood. Only by choosing the right explosion-proof motor can the safety of use be guaranteed and no waste of resources